Alternative energy automotive vehicles may be powered by hydrogen fuel or other alternative compressed fuels. One challenge with alternative fuel vehicles and hydrogen fuel cell vehicles in particular is packaging and storing enough fuel on the vehicle in order to achieve an acceptable driving range, while still maintaining cargo and passenger capacity as well as the vehicle's aesthetic design. For example, in order to have a vehicle driving range of at least 200 miles, a fuel cell vehicle may require approximately 160 liters to 235 liters of vehicle space for hydrogen fuel depending on the storage pressure.
Additionally, the compressed fuels must be stored at high pressures. For example, hydrogen fuel may be stored at a pressure of 5,000 pounds per square inch (psi) and even up to pressures greater than 10,000 psi. In order to withstand this pressure, the fuel storage tanks may be a pressure vessel having a cylindrical shape in order to evenly distribute the stress and increase the strength. The cylindrical-shaped fuel storage tanks further exacerbate the challenges of packaging alternative fuels since the pressure vessel is unable to conform to the available space within the vehicle, unlike conventional gasoline fuel tanks.
In order to package cylindrical fuel storage tanks with enough capacity, many configurations have been considered. For example, fuel storage tanks may be mounted under the hood of a vehicle. However, this design still may store significantly less than the target fuel capacity unless the hood and aesthetic look of the vehicle is modified.
Fuel storage tanks may also be mounted in the cargo or passenger area of a vehicle. While this design would allow more fuel capacity, the cargo utilization or passenger capacity of the vehicle would be adversely affected.